In this study, waste nutrient solution (WNS) was used as a catholyte in a bioelectrochemical cell to directly produce hydrogen peroxide (H₂O₂), after which the H₂O₂- containing WNS was integrated with the downstream UV oxidation process to meet quality standards for reuse. The generated current in the bioelectrochemical cell was successfully utilized at the cathode to produce H₂O₂ in WNS using a two-electron oxygen reduction reaction with different reaction times. The cathodic reaction time with the highest H₂O₂ production (504 ± 5.2 mg l⁻¹) was 48 h, followed by that obtained from 24 h (368 ± 4.1 mg l⁻¹), 12 h (158.8 ± 2.4 mg l⁻¹), and 6 h (121.1 ± 4.1 mg l⁻¹) reaction times. During H₂O₂ generation, calcium, magnesium, and phosphate in the WNS were recovered in the form of precipitates under alkaline conditions. The H₂O₂-containing WNS was further treated with different UV doses. After UV/H₂O₂ treatment, excitation-emission matrix and molecular weight distribution analyses demonstrated that aromatic compounds were reduced. Moreover, the gene expressions of sul1 (up to 95.65%), tetG (up to 93.88%), and aadA (up to 95.32%) were clearly downregulated compared with those of a control sample. Finally, a high disinfection efficiency was achieved with higher UV doses, resulting in successful seed germination. Thus, our results indicate that the developed method can be a promising process for reusing WNS in hydroponic systems.

本研究利用废弃营养液（WNS）作为生物电化学电池的阴极电解液，直接产生过氧化氢（H ₂ O ₂ ），然后生成H ₂ O ₂ - 含有 WNS 与下游 UV 氧化工艺集成，以满足再利用的质量标准。通过不同反应时间的双电子氧还原反应，在WNS中成功地利用生物电化学电池中产生的电流在阴极产生H ₂ O ₂ 。 H ₂ O ₂ 产量最高（504 ± 5.2 mg l ⁻¹ ）的阴极反应时间为 48 小时，其次为 24 小时（ 368 ± 4.1 mg l ⁻¹ )、12 小时 (158.8 ± 2.4 mg l ⁻¹ ) 和 6 小时 (121.1 ± 4.1 mg l ⁻¹ ) 反应时间。在 H ₂ O ₂ 生成过程中，WNS 中的钙、镁和磷酸盐在碱性条件下以沉淀物的形式被回收。含有H ₂ O ₂ 的WNS进一步用不同的UV剂量进行处理。 UV/H ₂ O ₂ 处理后，激发发射矩阵和分子量分布分析表明芳香族化合物减少。此外，与对照样本相比，sul1（高达95.65％）、tetG（高达93.88％）和aadA（高达95.32％）的基因表达明显下调。最后，通过更高的紫外线剂量实现了高消毒效率，从而使种子成功发芽。因此，我们的结果表明，所开发的方法可能是在水培系统中重复使用 WNS 的有前途的过程。